<template>
  <div class="star" :class="starType">
    <span class="star-item" v-for="(itemClass, index) in itemClasses" :key="index" :class="itemClass"></span>
  </div>
</template>
<script>
const LENGTH = 5
const CLS_ON = 'on'
const CLS_HALF = 'half'
const CLS_OFF = 'off'

// 测试
export default {
  props: {
    score: {
      type: Number
    },
    size: {
      type: Number
    }
  },
  computed: {
    starType () {
      return 'star-' + this.size
    },
    itemClasses () {
      let result = []
      // 计算是否有半星
      let score = Math.floor(this.score * 2) / 2
      let hasDecimal = score % 1 !== 0
      let intege = Math.floor(score)
      for (var i = 0; i < intege; i++) {
        result.push(CLS_ON)
      }
      if (hasDecimal) {
        result.push(CLS_HALF)
      }
      while (result.length < LENGTH) {
        result.push(CLS_OFF)
      }
      return result
    }
  }
}
</script>
<style lang="stylus" rel="stylesheet/stylus">
  @import '~common/stylus/mixin'
  .star
    font-size: 0;
    .star-item
      display: inline-block;
      background-repeat: no-repeat;
    &.star-48
      .star-item
        width: 20px;
        height: 20px;
        margin-right: 22px;
        background-size: 20px 20px;
        &:last-child
          margin-right: 0;
        &.on
          bg-image('star48_on');
        &.half
          bg-image('star48_half');
        &.off
          bg-image('star48_off');
    &.star-36
      .star-item
        width: 15px;
        height: 15px;
        margin-right: 6px;
        background-size: 15px 15px;
        &:last-child
          margin-right: 0;
        &.on
          bg-image('star36_on');
        &.half
          bg-image('star36_half');
        &.off
          bg-image('star36_off');
    &.star-24
      .star-item
        width: 10px;
        height: 10px;
        margin-right: 3px;
        background-size: 10px 10px;
        &:last-child
          margin-right: 0;
        &.on
          bg-image('star24_on');
        &.half
          bg-image('star24_half');
        &.off
          bg-image('star24_off');
</style>